N75 Boost control help

[madpugger]

Hi guys, I was getting the S2 mapped yesterday and we found that A) the Turbo dynamics WG spring that I was given as a 'stage 1' is actually over 2 Barg! and B) my N75 isn't operating.

I checked continuity from the switched (earth?) from the ECU plug to the N75 one and it is good.

Checked for 12v and appear to have none. Should there be 12v with the ign on but engine not running? Any idea of what fuse supplies it?

Cheers

[prj]

You can do an output test with vag com with ignition on to make it click.
Try it, select the test, then go and listen.
If it clicks, it's probably fine. You are not supposed to have 12V there with ignition on.

Who mapped your car?

[madpugger]

There is 12v with engine running, I thought it was supposed to be there without engine running...

Vag Com will do nothing sorry, this S2 is on VEMS. I see a resistance change when doing an output test so I guess the next test is 12v straight to the N75 to see if it clicks, then try changing the channel in VEMS.

Car was not actually mapped as the base map from Peter/Jamo were spot on, he was just checking things over and were were going to up the boost as run in is well under way...

[epic]

I'd personally stay well clear of the Turbo Dynamics springs. I tried them and they all gave way to much boost. I heard this was why they were selling them off cheap recently

[max_s2]

With VEMS newer firmwares you can do output as well as on motronic with VAG. Check if your outputs are correctly setup in "Output channels" and check alos if selected output channel matches the right pinouts (for example, set your injgroup outputs in "Injector outputs visual" dialog).

[max_s2]

First check these settings that they operate with the right pinout and then Output channels. See attachment.

[UrS4boy]

N75 activation and info

Hi guys, I was getting the S2 mapped yesterday and we found that A) the Turbo dynamics WG spring that I was given as a 'stage 1' is actually over 2 Barg! and B) my N75 isn't operating.I checked continuity from the switched (earth?) from the ECU plug to the N75 one and it is good.Checked for 12v and appear to have none. Should there be 12v with the ign on but engine not running? Any idea of what fuse supplies it? Cheers

The N75 wastegate frequency valve is energized by the J17 fuel pump relay. The fuel pump relay is only energized by the ECU (Motronic anyway, not sure how your VEMS is set-up) when the ECU gets a signal from the G28 engine speed sensor that tells the ECU that the RPM > 13. The fuse involved is the S75 (at least for a C4 AAN)

General N75 info HERE

[madpugger]

Cheers, I did this test yesterday but there is no 12v with the engine off so when testing the sov does not operate, although I do see a resistance change to earth on the output channel wire.

Interestingly, my WGFV uses the same channel but pinout 17, and my fuel pump also works off channel 5 and ISV on 6...

[Thuppu]

Hard to find Vems econoseal to motronic 55 pinouts... What is the right pin for AAN Vems boost control? Is it pin 6 like in the max_S2 post above?